1.1 Background: Respiratory syncytial virus (RSV) is the most common pathogen that causes acute lower respiratory tract infection in infants and young children. However, very rarely, RSV can induce acute respiratory distress syndrome (ARDS) in immunocompetent adults. Unluckily, optimal management has not been well-known for this eventually fatal condition. We report a case of fatal RSV-induced ARDS occurring in a previously healthy man. 

1.2 Observation: A 42-year-old male was admitted to the Emergency Department with cough, dyspnea and fever. His previous clinical history showed no relevant disease. Pulmonary radiology revealed diffuse ground-glass opacities in both lung fields. Lab analysis revealed high inflammation markers, witness of infection. After 2 days, the patient developed ARDS, we transferred it in the Intensive Care Unit. Microbiological investigation reported positivity of RSV PCR. Furthermore, the patient had a negative serology for HIV and normal T CD4+ lymphocyte counts. Despite treatment with Ribavirin and respiratory support, the patient died of pulmonary embolism. 

1.3 Conclusion: Thus, RSV infection should be considered a possible though rare cause of ARDS in adulthood in particular when computed tomography (CT) chest find diffuse ground-glass opacities.